There has been a number of alternative technologies developed for controlling a device or process, for use by disabled persons. While these technologies need not be used solely by disabled persons, they have been developed with the particular physical limitations of disabled persons in mind. U.S. Pat. No. 5,233,662 (Christensen 1993) and U.S. Pat. No. 5,523,745 (Fortune et al 1996) describe tongue operated apparatus. U.S. Pat. No. 4,865,610 (Muller 1989) describes a mouthpiece into which signals are input by sucking or blowing. U.S. Pat. No. 5,812,978 (Nolan 1998) describes the use of a voice control apparatus.
The use of signals from switches or sensors to control functional electrical stimulation (FES) of paralyzed muscles is known. Use of a shoulder position sensor to control wrist extension via an implanted FES stimulator has been described (Vodovnik, L (1971) “Development of Orthotic Systems using functional electrical stimulation and myo-electric control,” Progress Report, University of Ljubljana, prepared for U.S. Dept. of Health Education and Welfare Social and Rehabilitation Service, under contract No. SRS-YUGO 23-68). Use of contact switches placed in the shoe to control FES of the leg muscles has been described (Liberson W. T., Holmquest H. J. Scott D, Dow, M. (1961) “Functional electrotherapy: stimulation of the peroneal nerve synchronized with the swing phase of the gait of hemiplegic patients.”
Archives of Physical and Medical Rehabilitation 42: 101-105). Shoulder sensors have also been used to control hand opening and pinch-grip (Peckham, P. K, Marsolais, E. B. & Mortimer, J. T. (1980) J. Hand Surgery, 5,462-469; Petrovsky, J. S. (1985) Hand Control System, EP-145504-A, CA1263446-A, U.S. Pat. No. 4,558,704; Peckham, P. H. & Keith, M. W. (1992) “Motor prostheses for restoration of upper extremity function” In “Neural Prostheses: Replacing Motor Function After Disease or Disability” eds.: Stein, R. B., Peckham, P. H. & Popovic, D. B. New York: Oxford University Press. A wrist position sensor has been used to control FES of leg muscles (Prochazka, A. & Wiles, C. M. (1983) “Electrical stimulation of paretic leg muscles in man, allowing feedback-controlled movements to be generated from the wrist” J. Physiol. 343, 20P). A switch mounted on a watch band has been used to trigger FES-evoked pinch-grip (Handa, Y., Itchie, M, Handa, T., Takahashi, K Saito, C., Kameyama, J. & Hoshimiya, N. (1989) “FES-control of multi-joint system in the paralysed upper limb.” Osaka Int. Workshop on FNS. pp. 91-95.). A multi-component device in which wrist position sensors are used to stimulate FES evoked pinch-grip has also been described (Crago, P. E., Peckham, P. H., Mansour, J. M., Lan, N., Kilgore, K. and Chizeck, H. J. (1991) a, b, c,) “Functional neuromuscular stimulation for restoration of hand grasp.” NIH Contract NO1-NS-9-2356 7th, 8th & 9th Progress Reports, June, September & December, 1991; Crago, P. E., Peckham, P. H. Mansour, J. M., Lan, N., Kilgore, K. and Chizeck, H. J. (1992). “Functional neuromuscular stimulation for restoration of hand grasp.” NIH Contract NO1-NS-9-2356. 10th, 11th & 12th Progress Reports, March, June, September, 1992; Peckham, P. H. & Keith, M. W. (1992) “Motor prostheses for restoration of upper extremity function” In: Neural Prostheses: Replacing Motor Function After Disease or Disability, eds.: Stein, R. B., Peckham, P. H. 8c Popovic, D. B. New York: Oxford University Press). An FES garment is described (Prochazka, A., Wieler, M. Kenwell, Z. & Gauthier M. J. (1996) U.S. Pat. No. 5,562,707 in which FES is controlled by signals from proximity detectors which transduce relative motions of an adjacent limb segment such as the hand by monitoring changes in electric or magnetic fields, or changes in the intensity of sound or light transmitted from the adjacent limb segment or changes in the stretching of skin underlying the garment.